1. Field of the Invention
This invention relates to Fe-based alloy powder, an Fe-based sintered body with high-corrosion resistance and a method for producing the Fe-based sintered body with high-corrosion resistance by using the aforementioned Fe-based alloy powder.
2. Description of the Prior Art
A powder metallurgical method, that is a process consisting in compacting metal powder (inclusive alloy powder) into a desired shape and sintering the obtained compact has been widely utilized as one of manufacturing methods for metallic products.
Generally, in a case of manufacturing metallic products required for high corrosion resistance, metal powder excellent in the corrosion resistance, such as stainless steel powder is used. However, there is a characteristic and difficult problem in the powder-sintered body as compared with metallic products made from ingot steel.
Namely, in the case of the powder-sintered body, there is the problem in that open pores remain in the sintered body (product), and rust is apt to start and proceed from the open pores. Namely, a difference arises in oxygen concentration between inside and outside of the open pore, and crevice corrosion develops owing to the the difference in the oxygen concentration.
Accordingly, the products manufactured through the powder-sintering process is inferior to the metallic products made from the ingot steel in the corrosion resistance in any rate.